The present invention relates to variable resistors and, more particularly, to a mechanism enabling a sliding motion of a sliding element along a winding resistance body formed on an insulating substrate plate by such means as evaporation or printing techniques in a manner providing a linear output.
A conventional type of variable resistor has generally been constituted by forming a resistance body 3 on a substrate plate 1, as shown in FIG. 1. In order to obtain a larger changing rate for the value of the resistance, the resistance body 3 is typically made to extend in a winding or back and forth pattern over the path of a movable slider 4 adapted to slide along the central section of the sliding body 3, as shown by the broken lines.
Therefore, the output of the variable resistor varies inconveniently in a stepped manner in proportion to the distance travelled by the slider, as shown by a full line in FIG. 1, resulting in poor resolution.
It is therefore an object of the invention to overcome the above described shortcoming of the prior art.